The present invention relates generally to a radio device operable to communicate data pursuant to a first data service, such as in an HDR (High Data Rate) system, and to communicate data pursuant to a second data service, such as in an IS-95/IS-2000 system. More particularly, the present invention relates to apparatus, and an associated method, by which to permit simultaneous reception at the radio device of data generated during operation of both of the data services. Through operation of an embodiment of the present invention, an existing practice by which a hard handoff at a radio device of communications from a first data channel to a second data channel is obviated. Interruption of reception of data therefore does not occur, and improved data communication results
A communication system is formed, at a minimum, of a sending station and a receiving station interconnected by way of a communication channel. Information generated at the sending station is communicated to the receiving station upon the communication channel. A wide variety of different types of communication systems have been developed and are regularly utilized to effectuate communication of information between sending and receiving stations.
Advancements in communication technologies have permitted the development, and construction, of new types of communication systems. A radio communication system is exemplary of a type of communication system which has benefited from advancements in communication technologies. A communication channel formed between the sending and receiving stations of a radio communication system are defined upon a radio link. Because a radio link is utilized to form the communication channel, the conventional need to utilize wireline connections between the sending and receiving stations is obviated. Increased communication mobility is, as a result, inherent in a radio communication system in contrast to a conventional wireline system.
The communication capacity of a radio communication system, however, is sometimes constricted as a result of bandwidth limitations. Only a limited amount of the electromagnetic spectrum is typically allocated to be used by a particular radio communication system and upon which communication channels can be defined. Communication capacity increase of a radio communication system is, therefore, sometimes limited by such allocation of bandwidth. Increase of the communication capacity of the radio communication system, therefore, is sometimes only possible by increasing the efficiency by which the allocated spectrum is used.
Digital communication techniques are amongst the advancements in communication technologies which have advantageously been implemented in various communication systems. Digital communication techniques permit the bandwidth efficiency of communications upon a communication channel in a communication system to be increased. Due to the particular need to efficiently utilize the bandwidth allocated in a radio communication system, the use of such digital techniques is particularly advantageously utilized in a radio communication system.
A cellular communication system is exemplary of a radio communication system in which digital communication techniques are regularly utilized. Various cellular standards have been promulgated, and cellular communication systems are generally constructed to be operable in compliance with a selected one, or more, of the standards. For instance, a cellular standard, referred to as the IS-95/IS-2000 standard defines a CDMA (Code-Division, Multiple Access)-based cellular communication system. Cellular communication systems in compliance with this standard have been installed throughout wide geographical areas.
Users of a cellular communication system are able to communicate telephonically by way of mobile stations to communicate voice information, herein referred to also as voice data. Utilization of digital communication techniques has also facilitated the communication of other types of data, herein referred to as non-voice data. Various standards have also been developed which pertain to the communication of non-voice data. For instance, an HDR (High Data Rate) data communication system standard has been promulgated. A communication system constructed to comply with the HDR standard provides for the communication of non-voice information at high data rates.
Mobile stations have been constructed to permit communication therethrough of both voice, and other, data generated pursuant to operation of an IS-95/IS-2000 system as well as also non-voice, and other, data generated during operation of an HDR system. The IS-2000 system, for instance, is capable of data rates of 614.4 kbps while HDR data rates approach 2.45 Mbps. Data generated during operation of the HDR system is transmitted to a mobile station within a first frequency band, and IS-95/IS-2000 data transmitted to the mobile station is transmitted within a second frequency band. Conventional mobile terminals operable to receive data generated pursuant to data generated pursuant to both of the systems include a receive portion which must effectuate a hard handover between frequency bands, alternately to receive the data generated during operation of the separate systems. For instance, the mobile terminal is normally tuned to the frequency band upon which the HDR data is transmitted but, a hard handover to the frequency band upon which the IS-95/IS-2000 data is transmitted is effectuated at selected intervals to detect transmission of information such as IS-95/IS-2000 where the paging channel carries targeted user information. Subsequent to the hard handover to the frequency band upon which the data is transmitted, the mobile terminal is unable to detect the data generated pursuant to operation of the HDR data system. Interruption of the reception of the HDR data results.
If a manner could be provided by which to permit simultaneous reception of data generated during operation of both systems, improved communication would be permitted.
It is in light of this background information related to the communication of data in a radio communication system that the significant improvements of the present invention have evolved.
The present invention, accordingly, advantageously provides apparatus, and an associated method, for a radio device to facilitate radio reception thereat of both first data generated pursuant to a first data service and second data generated pursuant to a second data service.
Through operation of an embodiment of the present invention, a manner is provided by which to permit simultaneous reception at the radio device of both the first data and the second data. Simultaneous reception of both the first data and the second data is achieved by obviating the need to perform a hard handoff of communications at the radio device to receive only alternately the first data and the second data. Because simultaneous reception of the first data and the second data is permitted, a communication interruption due to the conventional hard handoff of communications does not occur.
In one aspect of the present invention, a receive portion of a radio device is provided with a first RF (Radio Frequency) received chain and a second RF (Radio Frequency) receive chain positioned in parallel and permitting of simultaneous operation. During normal operation, both of the receive chains are together operable as a diversity receiver to receive first data generated pursuant to a first communication service. At selected intervals, one of the receive chains is tuned to a paging channel associated with with IS-95/IS-2000 with a second communication service. When tuned to the frequency channel associated with the second communication service, a determination is made as to whether second data is to be communicated to the mobile terminal. If so, the receive portion, already tuned to the frequency band upon which the second data is to be communicated, remains tuned to such frequency band. Otherwise, the receive portion is retuned back to the frequency band upon which the non-voice data is communicated. Although diversity reception is no longer performed when one of the receive portions is retuned to the frequency band upon which the second data is to be communicated, the other of the RF receive portions remains tuned to the frequency band upon which the first data is communicated. Thereby, continuous reception of the first data is permitted.
In another aspect of the present invention, the mobile terminal notifies the sender of the first data an indication of the operation of the receive portions either together as a diversity receiver or tuned separately to the two different frequency bands. When the receive portions are together operable as a diversity receiver, first data is permitted to be provided to the mobile terminal at an equal or higher rate band than when only one of the RF receive portions is tuned to the frequency band upon which the first data is communicated.
In another aspect of the present invention, one of the RF receive portions is periodically tuned out of the frequency band associated with the second data service and to a paging channel defined pursuant to the second data service. Paging signals are transmitted upon the paging channel to alert the mobile terminal of subsequent second data to be communicated thereto. If a paging signal is detected, the receive portion is retuned out of the paging channel and to a communication channel, within the frequency band associated with the second data service, upon which the second data is thereafter communicated. If, conversely, the paging signal is not detected, the receive portion is retuned back to the frequency band associated with the first data service, and the mobile terminal is again operated as a diversity receiver.
In another aspect of the present invention, when a paging signal is detected, the transmit portion of the mobile terminal is also caused to be tuned to the frequency band associated with the second data service. Thereby, the mobile terminal is operable both to receive and to send voice data pursuant to the second data service.
In one implementation, a communication station, such as a mobile station, is operable pursuant to an IS-95/IS-2000 cellular communication system and also pursuant to an HDR (High Data Rate) data system. The mobile station is permitted, through operation of an embodiment of the present invention, simultaneously to receive both data generated pursuant to the IS-95/IS-2000 system and data generated pursuant to the HDR data system. The communication station includes a first and a second RF (Radio Frequency) receive portions area. The first RF receive portion is tunable to a frequency band associated with the HDR data service. And, the second RF receive portion is tunable both to the frequency band associated with the HDR data service and also to a frequency band associated with the IS-95/IS-2000 service. The second RF receive portion is selectably tuned to the frequency band associated with the IS-95/IS-2000 service, thereby to permit simultaneous reception of both the HDR data and the IS-95/IS-2000 data.
In these and other aspects, therefore, apparatus, and an associated method, is provided for a radio device operable pursuant to a first data service and pursuant to a second data service. The apparatus is selectably operable simultaneously to receive data generated pursuant to the first data service and second data generated pursuant to the second data service. A first RF (Radio Frequency) receive portion is at least selectably tunable to a channel upon which the first data generated during operation of the first data service is transmitted to the radio device. A second RF (Radio Frequency) receive portion is at least selectably tunable to the channel upon which the first data generated during operation of the first data service is transmitted and also to a channel upon which the second data generated pursuant to the second data service is transmitted. When tuned to the channel upon which the second data is transmitted, simultaneous reception of both the first data and the second data is effectuated.
A more complete appreciation of the present invention and the scope thereof can be obtained from the accompanying drawings which are briefly summarized below, the following detailed description of the presently-preferred embodiments of the invention, and the appended claims.